Primula plant named ‘Thirtyone’

ABSTRACT

A new and distinct cultivar of  Primula  plant named ‘Thirtyone’, characterized by its upright plant habit; vigorous growth habit; freely flowering habit; and light purple-colored flowers that are held above and beyond the foliage on strong peduncles.

Botanical designation: Primula filchnera×Primula sinensis.

Cultivar denomination: ‘Thirtyone’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Primula,botanically known as Primula filchnera×Primula sinensis, and hereinafterreferred to by the name ‘Thirtyone’.

The new Primula is a product of a planned breeding program conducted bythe Inventors in Chiba, Japan. The objective of the breeding program isto create new vigorous Primula cultivars with strong growth and earlyflowering habits.

The new Primula originated from a cross-pollination made by theInventors in April, 2002 in Chiba, Japan of an unnamed proprietaryselection of Primula filchnera, not patented, as the female, or seed,parent with an unnamed proprietary selection of Primula sinensis, notpatented, as the male, or pollen, parent. The new Primula was discoveredand selected by the Inventors as a single flowering plant within theprogeny of the stated cross-pollination in a controlled environment inChiba, Japan in August, 2002.

Asexual reproduction of the new Primula by micropropagation in acontrolled environment in Chiba, Japan since October, 2002 has shownthat the unique features of this new Primula are stable and reproducedtrue to type in successive generations.

SUMMARY OF THE INVENTION

The cultivar Thirtyone has not been observed under all possibleenvironmental conditions. The phenotype may vary somewhat withvariations in environment and cultural practices such as temperature,daylength and light intensity without, however, any variance ingenotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘Thirtyone’. These characteristics incombination distinguish ‘Thirtyone’ as a new and distinct cultivar ofPrimula:

-   -   1. Upright plant habit.    -   2. Vigorous growth habit.    -   3. Freely flowering habit.    -   4. Light purple-colored flowers that are held above and beyond        the foliage on strong peduncles.

Plants of the new Primula can be compared to plants of the female parentselection. Plants of the new Primula differ from plants of the femaleparent selection in the following characteristics:

-   -   1. Leaves of plants of the new Primula have less deeply incised        margins than leaves of plants of the female parent selection.    -   2. Flowers of the new Primula and the female parent selection        differ in flowers color.    -   3. Plants of the new Primula are more high temperature tolerant        than plants of the female parent selection.

Plants of the new Primula can be compared to plants of the male parentselection. Plants of the new Primula differ from plants of the maleparent selection in the following characteristics:

-   -   1. Leaves of plants of the new Primula have more deeply incised        margins than leaves of plants of the male parent selection.    -   2. Plants of the new Primula are more freely flowering than        plants of the male parent selection.    -   3. Plants of the new Primula and the male parent selection        differ in flower color.

Plants of the new Primula can be compared to plants of the Primulasinensis cultivar Fanfare, not patented. In side-by-side comparisonsconducted in Chiba, Japan, plants of the new Primula differed fromplants of the cultivar Fanfare in the following characteristics:

-   -   1. Plants of the new Primula were taller than plants of the        cultivar Fanfare.    -   2. Leaves of plants of the new Primula were larger than leaves        of plants of the cultivar Fanfare.    -   3. Flowers of plants of the new Primula were larger than flowers        of plants of the cultivar Fanfare.    -   4. Plants of the new Primula and the cultivar Fanfare differed        in petal color as plants of the cultivar Fanfare had        white-colored petals.    -   5. Plants of the new Primula and the cultivar Fanfare differed        in sepal color as plants of the cultivar Fanfare had red        purple-colored sepals.    -   6. Plants of the new Primula had longer and thicker peduncles        than plants of the cultivar Fanfare,

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearanceof the new Primula, showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description which accurately describe the colors ofthe new Primula.

The photograph on the first sheet comprises a side perspective view of atypical flowering plant of ‘Thirtyone’ grown in a container.

The photograph on the second sheet is a close-up view of typical flowersof ‘Thirtyone’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurementsand values describe plants grown in Tokyo, Japan in 15-cm containers ina glass-covered greenhouse during the winter and under conditions whichclosely approximate commercial production. During the production of theplants, day temperatures ranged from 10° C. to 35° C., nighttemperatures ranged from 0° C. to 20° C. and light levels averaged 50kilolux. Plants were about six months old when the photographs and thedescription were taken. In the description, color references are made toThe Royal Horticultural Society Colour Chart, 2001 Edition, except wheregeneral terms of ordinary dictionary significance are used.

-   Botanical classification: Primula filchnera×Primula sinensis    cultivar Thirtyone.-   Parentage:    -   -   Female, or seed, parent.—Unnamed proprietary selection of            Primula filchnera, not patented.        -   Male, or pollen, parent.—Unnamed proprietary selection of            Primula sinensis, not patented.-   Propagation:    -   -   Type.—By tissue culture.        -   Time to initiate roots.—About three weeks at 18° C. to 25°            C.        -   Time to produce a rooted cutting.—About five to six weeks at            18° C. to 25° C.        -   Root description.—Fibrous; white and red purple in color.        -   Rooting habit.—Moderately freely branching; moderately            dense.-   Plant description:    -   -   Plant habit.—Upright and uniform plant habit; inverted            triangle. Vigorous growth habit. Freely basal branching;            about ten to twelve branches develop per plant.        -   Plant height.—About 21 cm.        -   Plant width (spread).—About 25 cm to 30 cm.-   Foliage description:    -   -   Arrangement.—Basal, simple.        -   Length.—About 14 cm.        -   Width.—About 13 cm.        -   Shape.—Roughly cordate.        -   Apex.—Obtuse.        -   Base.—Acute.        -   Margin.—Crenate.        -   Texture, upper and lower surfaces.—Pubescent; rugose.        -   Venation pattern.—Pinnate.        -   Color.—Developing and fully expanded leaves, upper surface:            137B; venation, 144A, towards the base, 60A. Developing and            fully expanded leaves, lower surface: 139C; towards the            base, 61A; venation: 143C, towards the base, 60A.        -   Petiole length.—About 13 cm.        -   Petiole diameter.—About 7 mm.        -   Petiole texture, upper and lower surfaces.—Pubescent.        -   Petiole color, upper and lower surfaces.—60A.-   Flower description:    -   -   Flower type/habit.—Single rounded and salverform flowers            arranged on umbels on upright and strong peduncles; flowers            face mostly upright. Freely flowering habit with about 5 to            15 flowers per umbel.        -   Fragrance.—Fragrant, not pleasant; typical of species.        -   Natural flowering season.—Flowering occurs naturally during            the spring in Japan. Flowers last about one to two weeks on            the plant; flowers not persistent.        -   Flower buds.—Height: About 1.2 cm to 1.7 cm. Diameter: About            4 to 5 mm. Shape: Elliptic. Color: Between 144A and 200A.        -   Inflorescence height.—About 4 cm to 10 cm.        -   Inflorescence width.—About 5 cm to 12 cm.        -   Flower diameter.—About 4 cm.        -   Flower depth.—About 2 cm.        -   Petals.—Quantity per flower: About five in a single whorl.            Length (including tube): About 1.5 cm. Width: About 1.1 cm            to 1.4 cm. Shape: Obcordate. Apex: Shallowly emarginate.            Margin: Finely crenate. Texture, upper and lower surfaces:            Smooth, glabrous. Color: Developing petals, upper and lower            surfaces: Towards the margins, N80A; towards the center,            N80B; at the center, 155B. Fully expanded petals, upper            surface: Towards the margins, N80A to N80B; towards the            center, 77C to 77D to N155B; at the center, N144A. Fully            expanded petals, lower surface: Towards the margins, N80A;            towards the center, 77DB; at the center, N155B.        -   Sepals.—Quantity per flower: Typically five fused in a            single whorl. Length: About 1 cm to 1.5 cm. Width: About 0.8            cm to 1.2 cm. Shape: Lanceolate. Apex: Acute. Margin:            Serrate. Texture, upper surface: Smooth, glabrous. Texture,            lower surface: Pubescent. Color, upper and lower surfaces:            Between 144A and 200A.        -   Peduncles.—Length: About 15 cm to 21 cm. Diameter: About            6 mm. Orientation: Mostly erect. Strength: Strong. Texture:            Pubescent; rough. Color: 178A.        -   Pedicels.—Length: About 2 cm to 5 cm. Diameter: About            1.5 mm. Orientation: Outward. Strength: Moderately strong.            Texture: Pubescent. Color: Between 148B and 178A.        -   Reproductive organs.—Stamens: Quantity/arrangement: Four per            flower. Anther shape: Oblong. Anther length: About 2 mm.            Anther color: 2C. Pollen amount: None observed. Pistils:            Quantity: One per flower. Pistil length: About 1 cm. Stigma            shape: Dome-like. Stigma color: 149A. Style length: About            5 mm. Style color: 149D. Ovary color: 144C. Fruits/seed:            Fruit and seed development have not been observed.-   Garden performance: Plants of the new Primula have been observed to    tolerate wind, rain and temperatures from about −5° C. to about 40°    C.-   Pathogen/pest resistance: Plants of the new Primula have not been    observed to be resistant to pathogens and pests common to Primulas.

1. A new and distinct Primula plant named ‘Thirtyone’ as illustrated anddescribed.